The present invention relates to respirators, and specifically to a modular respirator system and method of converting components between respirators.
Respirators for providing a breathable air supply to a wearer are well known and have been used for many years. Such respirators include masks used by firefighters, in the military, and in industrial applications where the air supply may be contaminated. In addition to providing a clean air source to the nose and mouth for breathing, full face shields also protect the eyes and face from harmful or irritating gases and other substances. Such masks typically include a transparent face shield and may also include mounts for accepting detachable and replaceable filter elements or connectors to air supplies.
There are a number of specific types of respirators in common use, including filtering facepieces, half face masks or half facepiece respirators, full facepiece respirators, hood respirators, or hood respirators combined with a facepiece. Each respirator is of a fixed, single design, lacking modularity and interchangeability.
Hood respirator examples are described in U.S. Pat. No. 4,619,254 to Moretti, et al., which discloses a protective respirator hood for use with half or full-face respirator masks as well as for use as a supplied air respirator hood. A portion of the flexible hood material provided is integrated with a respirator that is then sealed over the nose and the mouth of the user.
Other examples of protective respirator hoods include those described in U.S. Pat. No. 4,484,575 to Brockway and U.S. Pat. No. 4,542,538 to Moretti. The Brockway patent describes a respirator hood with an integrated lens panel. The use of a negative pressure cartridge mounted through the lens of the respirator hood is also provided. The Moretti patent describes a respirator hood with a flexible transparent film accessory for use with an optical transparent lens panel. The transparent film array is disposable but is not designed to be used interchangeably with a different kind of hood or facepiece respirator. More importantly, the lens panel itself is integrated with the hood and has no modularity.
Minnesota Mining and Manufacturing Company, St. Paul, Minn., makes a variety of respirator assemblies (such as the 3M 6000 Series Respirators) that use disposable and interchangeable filters and cartridges for different kinds of environments. However, these respirators have no provision for interchangeable face shields.
Although some degree of component interchange may be achievable in each of the aforementioned protective respirators, such variations are limited to choosing from a range of selectable breathing elements, disposable lens shielding, and various forms of air supply.
The drawback in existing respirator hood designs that limits versatility of use and field configurability lies in the integrated nature of the hood and shield. No provision is made in the prior respirator designs to allow interchange of the hood element and the shield. Likewise, the prior art designs do not contemplate the interchangeability of the shield component between a respirator hood and a full facepiece respirator.